Issue 2 // Summer 2014 bristol.ac.uk/chemistry
JEWEL PURPOSE DISCOVER HOW SYNTHETIC DIAMONDS ARE CHANGING SCIENCE
HOPS & BEER: THE CHEMISTRY BEHIND THE SIMPLE PINT JAKE MACMILLAN: REMEMBERING A SCIENCE GREAT Welcome Also in this issue… Welcome to the second issue of Chemistry Explored. We’ve been delighted with the feedback from our first issue, so much so that we’ve decided to increase the pagination so we can bring you more news and features about the people and the work that makes Bristol such a great place to be. You’ll read about scientists sharing their enthusiasm for nanoscience and electrochemistry over a pint; a herbal walking tour with a chemistry focus; our prize-winning students; a retrospective on a science great and former News colleague; what our porters really think; Pint of Science 03 and a great deal more besides. Off to Princeton, Chemistry on film 04 As I write these words, we’re Bristol herb tour 05 approaching the end of another Skirting Science 06 successful academic year. Well done to We love Bristol 07 all our undergraduates who completed their exams, good luck to all those Features graduating this year, congratulations to The late, great Jake MacMillan 08 postgraduates who’ve won prizes at Diamonds are forever 10 conferences, and to staff who’ve won The chemistry of hops and beer 12 prestigious awards for their research. Meet the porter 14 With Open Day seeing thousands of Chemistry in numbers 15 hopeful students visit, we look forward Life through a lens 16 to welcoming even more people into our school. University of Bristol Group Editor Dan Linstead School of Chemistry Group Art Editor Will Slater Cantock’s Close, Bristol BS8 1TS, UK Director, Branded Content Julie Williams With thanks to Caroline Goode, Daniela Plana, Tel +44 (0)117 928 8201 Becky Brooks, Megan Shaw, Rose Silvester, Tom Web bris.ac.uk/chemistry Simpson, Rebecca Ingle, Lexy Miles-Hobbs, Email [email protected] Jenny Slaughter, Natalie Fey, Peter Crowther, Steph Harris Editor Aliya Mughal Photography Bhagesh Sachania To find out more about our courses and Unless otherwise indicated, copyright in this publication belongs to programmes, visit: bris.ac.uk/study the University of Bristol. Views expressed in Chemistry Explored do not necessarily reflect those of the University. The Editor reserves the right to edit Chemistry Explored is produced in contributions received. While care is taken to ensure accuracy of information, this cannot be guaranteed. Printed in the UK by William Gibbons. association with Immediate Media Professor Nick Norman Branded Content, Tower House, Head of the School Fairfax Street, Bristol BS1 3BN Tel +44 (0)117 927 9009 of Chemistry Web immediatecontent.co.uk
02 Chemistry Explored // Issue 2 update UPDATE The latest news from the School of Chemistry
Pint of Science brings the best academic scientists in the UK to local pubs so that they can explain their latest research From bench side to bar table Daniela Plana and Becky Brooks on how scientists are taking their subject to the pub
HOW can scientists engage more people On the first night Dr Rob Harniman and helping the University and Bristol’s wider in their research? By taking it to the pub! his PhD supervisor Professor Mervyn community relate to each other – here’s to That’s the solution which has proven Miles talked about their efforts to “touch a rerun next year. successful in London, Cambridge, Oxford the nanoworld”. Their simple, yet and now Bristol during a sell-out tour of thorough explanations of the different Find out what inspired Daniela, now a the country’s finest watering holes. microscopy techniques developed at Chemistry mentor, to take up science: No more is the seemingly alien Bristol University and around the world http://tinyurl.com/ncbcuec world of science the sole preserve of led to some inspired discussions between university researchers, thanks to the Pint scientists and non-scientists alike about of Science festival, which saw several of the possibilities for microelectronics and What is Pint of Science? our academics take their work into an medical diagnosis. Pint of Science sees some of the alternative environment. The resulting Professor David Fermin and his final world’s leading experts from six discussions led to some novel suggestions year PhD student David Parker talked countries and 21 cities travelling to for how science could be applied to the about “the electrochemist dream” pubs across the globe to discuss their everyday world. – championing renewable energies, latest findings with the public. Tickets for the Bristol events sold particularly solar, and the need to develop out before the doors even opened, with new photovoltaic materials that provide Find out more at: pintofscience.com a curious crowd eager to learn about cheap, efficient alternatives. Both were everything from nanotechnology to grilled by pub-goers on the green energy, to the brain and volcanoes. The credentials of such technologies and calls School of Chemistry was well represented to develop a complete, systematic approach in the ‘Chemistry and Physics’ themed to energy. evenings held at Channings in Clifton. The festival was hugely successful in
Chemistry Explored // Issue 2 03 UPDATE Chemistry on film You can take a look inside the School of Chemistry in a series of new videos in which staff and students show what’s on offer in some of the UK’s best teaching laboratories. The School offers up world-class lecturers and boasts an active student society which helps undergraduates develop the confidence and skills for life after university. n Chemistry in 60 seconds – Head of School Nick Norman reveals how he went from being a Bristol undergraduate to Professor of Inorganic Chemistry n Student views – hear what current students have to say about their time at Bristol n The student experience – explore the School of Chemistry labs, lecture theatres, library and social spaces bristol.ac.uk/chemistry/courses/undergraduate/videos/
PHD STUDENT HEADS TO PRINCETON INTERNATIONAL AWARDS, recognition from one of the UK’s leading agrochemical centres, and a prize-winning talk - that’s all before Megan Shaw completes her PhD at the Bristol Chemical Synthesis Centre for Doctoral Training. Megan’s research in the Bower research group sees her working with agri-business Syngenta, developing catalytic methods for the construction of novel types of complex molecules which are of interest to both the pharmaceutical and agrochemical industries. In 2013, she took the Synfacts poster prize at the 17th IUPAC International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis in Colorado, followed by first prize for her poster presentation at the Syngenta Chemistry Collaborative Research Conference back at Jealott’s Hill. In May 2014 Megan won first prize for her talk at the Third Year PhD Research Symposium. “My PhD gave me the opportunity to choose a research project I was interested in, and my experience at Bristol has increased my desire to continue working in academia,” says Megan, who in 2015 will head to Princeton University to become a postdoctoral researcher.
04 Chemistry Explored // Issue 2 UPDATE Bristol’s herb tour Rose Silvester goes on a tour of the city’s herb hotspots
One of the many wonderful things about science is the new perspectives it can provide, especially when combined with another area of expertise. Staff, students and friends of the School of Chemistry recently discovered this for themselves during a mini herbal tour of the city. Bristol-based medical herbalist Max Drake led the group of curious chemists from the doorstep of Cantock’s Close, home to the main Chemistry building, on through some of the city’s most notable hotspots, exploring some of the herbal and medicinal plants that are a constant source of inspiration for science. From the cultivated varieties in the raised bed at the entrance to Chemistry, to the Medical herbalist Max Drake (left) practices in Bristol at the common wild plants found on Brandon Urban Fringe Dispensary in Colston Street Hill, to the impressive herb garden just below Cabot Tower, Max gave the group 1 an education in how the flora and fauna we A4018 School of Close admire for their superficial qualities have Chemistry Cantock’s University of infinitely more to teach us. B4051 Park St Bristol As well as showing the group more Park Row than 30 different plants and telling them Berkeley Pl about their uses and some of the known active compounds involved, Max discussed Upper Berkeley Sq making tinctures and teas and how to dry Byron Pl The Route herbs. He talked about the relative merits 1 FlowerPark bed St at corner of Cantock’s Close and Woodland Road: Charlotte St of wild and cultivated varieties, how the 2 wildHill opium St lettuce, verbascum, 3 achillea, verbena bonariensis chemical understanding of plant remedies Charlotte St often lags behind their successful use, and Cabot Tower 2 Entrance to Brandon Hill Park from Berkeley Square: Park St the economics of gathering wild plants dandelion, herb robert, plantains: versus buying herbs already picked and dried. broadleaf, narrowleaf or ribwort
Max, who runs the nearby Urban Bridgewood Ln 3 Herb bed just below Cabot Great George St Tower: Fringe Dispensary, was an excellent guide 4 feverfew, borage, lemon balm, comfrey, St George Rd and showed how the School of Chemistry’s camomile, sage, mint, Froglavender, Ln fennel, angelica, nigella, rosemary, thyme, location gives us easy access to so many nepeta, tansy, hypericum Jacob’s Wells Steep fascinating plants and places. 4 Junction of several paths below 5 Brandon Brandon Hill the Tower and ponds: lime flowers on lime tree Read more about the herb walk on the Rd College Green 5 Wild area at the bottom of the hill:
Picture It… Chemistry blog: oxeye daisy, geranium, red clover College St College chempics.wordpress.com/2014/07/02/ Queen’s Parade herb-walk/
Open University students visit Bristol Open University students In total 73 students from chemistry of tin, using UV-Vis On the final day, the students from as far afield as Malaysia across the world including spectroscopy to calculate the got to put their newfound joined Chemistry’s teaching the UK and Europe, all in number of ligands on copper practical skills to the test laboratories over the summer their second year of study, complexes, synthesising making and using a Grignard as part of a three-day took part in experiments amides and honing their reagent for an organic residential course. investigating the redox titration skills. synthesis.
Chemistry Explored // IssueIssue1 2 0505 UPDATE
Skirting Science – getting girls Skirting Science is an award-winning event that inspires the next generation of into chemistry female scientists
Third year undergraduate student Lexy Miles-Hobbs describes her experience of developing outreach projects for the national Skirting Science event, aimed at encouraging more female school students to explore the scientific life
IT’S A COMMON MISCONCEPTION – pharmaceuticals, dyes, food, cleaning among young teenage girls that a career products and perfume. in chemistry is all about wearing a lab In the first part of the workshop we coat. They are often unaware of the broad observed how the smell and solubility of range of careers that chemistry can lead to. benzaldehyde and vanillin varied as a result Skirting Science has been inspiring 14 to of their structures, we demonstrated smells 17-year-old girls since 2009, showing them by spray tests and the students carried out a the many different opportunities that a solubility experiment. career in science can lead to. Applying the knowledge from the I’m about to go into my fourth and first half of the workshop, students final year of my studies and this summer discussed how structure relates to the I joined the Picture It… team to help properties of molecules and selected them develop outreach workshops for this likely candidate molecules for the year’s Skirting Science event at Broadoak different industries. College, Weston-super-Mare. It was really rewarding to share the We worked with three groups of 10 students’ enthusiasm. It was clear from students in our workshop and, using an the feedback that allowing the students to interactive talk, we introduced the girls make a link between science and everyday to chemistry in five different industries life helped to bring the topics into context.
Take the challenge For the pharmaceutical industry, the students were asked to Molecule A Molecule B look for candidate molecules which were soluble, containing a non-polar segment to cross the cell membrane but also a polar segment, so that the drug reaches systemic circulation and has a biological effect. They were also told that sometimes reduced side effects can be achieved by making the molecule more polar so that it can be excreted. The girls chose two likely candidates – can you identify which of the following fulfil the required properties?
Turn to page 13 for the answer, and for the latest entry from Picture It… 06 Chemistry Explored // Issue 2 UPDATE WE BRISTOL What the Chemistry hopefuls are saying about Bristol University…
EVERY YEAR, the University of Bristol welcomes thousands of students and their parents to a series of Open Days that give them a chance to see the places and people they could meet as a Bristol student. This summer, we asked a few Chemistry hopefuls what inspired them to check out Bristol.
Charlotte McDermot Amy Williams “I’m interested in “Bristol is a top university. Biochemistry and Chemistry. The labs were very I didn’t really know what impressive and the talks to expect from the Open were very informative. Bristol Day but I’m very impressed is very spread out and not with the staff, students and too built up, which is nice. facilities. I’m definitely going It doesn’t feel like a city.” home with a very positive impression of Bristol.”
Shiqing Zhou Chantelle Foster “The Chemistry labs are “Bristol is a top research really impressive. Bristol is university. It’s a lovely a very good city. I really like city, green and modern. I the environment – it’s a really especially enjoyed the view green city.” from the top of the Chemistry building! The course attracted me as in the first year you can do a third of modules from other sciences such as physics and maths.”
Laurence Alexander Daniel Morgan “The main things that “The course looked really have impressed me are good so I wanted to come the state-of-the-art labs here and check out the and the greenness of university and facilities. Bristol itself.” It’s a lovely location. I like the fact that it isn’t campus-based like some other universities.”
We want to hear from you! If you’ve anything you want to tell us about your experiences at Bristol University, or if you have any thoughts about Chemistry YOUR SAY Explored, then please email us at [email protected]. Chemistry Explored // Issue 2 07 SCIENTIFIC LIVES The late, great Jake MacMillan a tribute to a pioneer of synthetic biology
Tom Simpson remembers a towering figure in chemistry and plant physiology
Professor Jake MacMillan (here pictured with his wife Distinctions Anne) had a distinguished career which saw him 1973 President of the International Plant achieve the highest honours in chemistry Growth Substance Association 1978 Elected Fellow of the Royal Society 1978 Elected Corresponding Member of the American Society of Plant Physiology 1978 Flintoff Medal, Royal Society of Chemistry 1982 Research Medal, International Plant Growth 1987 Elected Distinguished Foreign Scholar of Mid-America Association of State Universities 1987 Elected Honorary Member of the Japanese Society for Chemical Regulation in Plants rofessor Jake MacMillan FRS passionate and gifted footballer, played for 1988 Royal Society of Chemistry (1924–2014), although an organic the then Scottish First Division team Third Hugo-Muller Lectureship and Medal chemist first and foremost, was one Lanark as an amateur, turning down offers P 1988 Royal Society of Chemistry of the United Kingdom’s most brilliant of professional football contracts in favour Award in Natural Product Chemistry interdisciplinary scientists. A young of a career in science. PhD student joining his group even in His first publication from his PhD 1988 American Society of Plant 1969 would have rubbed shoulders with studies with JD Loudon in Glasgow was on Physiology, Charles Reid Barnes Award fungal geneticists, plant physiologists and the identification of the 7-membered ring 1989 Elected Honorary Member of enzymologists as well as being exposed in the famous plant alkaloid, colchicine, the Botanical Society of America to internationally leading natural product isolated from the autumn crocus and used chemistry, advanced organic synthesis and widely for the treatment of gout. 1990 Wilson Baker Lecturer, mechanistic work and state-of-the-art In 1948 Jake joined the Frythe University of Bristol analytical methods including GC-MS. laboratory of ICI as part of a small but 1991 Foreign Associate of the US Jake was born and brought up in high-powered group of organic chemists National Academy of Sciences Lanarkshire, Scotland and was the first and microbiologists whose goal was to in his working class family to go to isolate novel biologically active metabolites 1995 Pergamon Phytochemical Prize university. He gained his BSc and PhD from fungi. An almost immediate fruit of at Glasgow University and, always a this work was the isolation from Penicillium
08 Chemistry Explored // Issue 2 Jake MacMillan and gibberellins The late professor was a world-renowned expert on plant growth hormones
In the 1960s the gibberellins (GAs) research of Jake MacMillan came to prominence. MacMillan was the international authority on the physiology and chemistry of the agriculturally important family of plant hormones, the gibberellins, and his contributions led the field for nearly four decades. He collaborated vigorously with botanists and griseofulvum of the fungistatic agent Above: Bristol’s Mass horticulturalists throughout the world and he has Spectrometry laboratory griseofulvin since widely used for treatment profoundly influenced research on the study of of dematophytic infections. The young growth control in higher plants. Scot had the temerity to tell Nobel Prize MacMillan also participated in determining the winner Sir Robert Robinson, at the time molecular structure of the GAs and developed a consultant for ICI, that his suggestions gas chromatography-mass spectrometry (GC- for the structure were wrong and on MS) methods to identify low abundance GAs in drawing his own proposed structure on the plant tissue. This led to the elucidation of the GA- blackboard, Sir Robert immediately jumped metabolic pathway, both in the fungus, Gibberella up and declared, “Problem solved!” fujikuroi, and intact seeds, enzyme preparations Jake then isolated the first of a group of from seeds and vegetative shoots of higher plants. compounds that were to become his lifelong There are now more than 125 GAs known in major interest – the gibberellins, compounds plants (many isolated and characterised in Bristol by produced in minute quantities in higher MacMillan and his many international collaborators). plants which are essential for their normal Gibberellic acid and synthetic derivatives have growth and development. gone on to be used extensively in agriculture and In 1963, Jake came to the University of horticulture. They reverse dwarf phenotypes in Bristol where he initiated a programme of plants such as maize and have found widespread work on fungal metabolites which remains use as an initiator of the germination of barley in the a mainstay of the Chemistry faculty to this malting process, increasing flowering, and in the day. The excellence and impact of Jake’s grape-growing industry to induce the production of work resulted in his election as a Fellow much bigger bunches of grapes. of the Royal Society (FRS) in 1978 and The influence of biological chemistry in Bristol the rare distinction of Foreign Associate of was given impetus by the return of Tom Simpson the US National Academy of Sciences in (1990-present). His research has focused on natural 1991. He received many other national and products and underpinning biosynthetic pathways, international awards, notably the Flintoff particularly the enzymatic processes and genetic Medal of the RSC in 1978, and both the control of polyketide biosynthesis. RSC Hugo-Muller Lectureship and Award for Natural Product Chemistry in 1988. Jake retired from the School of Chemistry in 1990 after seven years as Head of Organic Chemistry to take up a senior research fellowship at Long Ashton Research Station. He returned to Chemistry as a Senior Fellow in 2003. Jake was always a gentle but incredibly inspirational man. He is renowned for his many pithy comments, not least the MacMillan formula for success being the product of IQ and AQ, the latter being politely defined as application quotient. Jake MacMillan will be commemorated through the establishment of the MacMillan Postgraduate Prize in Organic and Biological Chemistry.
Chemistry Explored // Issue 2 09 INNOVATION
Professor Paul May of the University of Bristol DIAMONDS ARE
foreverRebecca Ingle meets Professor Paul May to look at the ways in which synthetic diamonds are revolutionising science
hen you think of diamonds, you wearing properties expert in gas-phase probably think of expensive of diamond for use chemistry, Professor W jewellery, maybe even drill in aircraft parts. Mike Ashfold in the bits or saws. You probably don’t think of However, it quickly 1893 School of Chemistry, quantum computing, laser optics, solar became apparent After discovering tiny ‘diamonds’ to help set up a new cells and even brain-computer interfaces. that, whilst people in a meteorite crater in Arizona, joint research project to For Professor Paul May, these are just some could successfully Dr Henri Moissan creates the make and study diamond of the exciting applications of what might create synthetic diamond simulant, Moissanite. films. Professor May seem to most like an inert, expensive rock. diamonds, at that had just finished his The idea for the Bristol Diamond Group time no one really understood how they PhD at Bristol in plasma processing of came from Professor Martin Lowson in grew, much less how to control the growth semiconductors, and so was in the right 1991, an aeronautical engineer with a process for such applications. place at the right time, with the right dream of being able to harness the hard- Professor Lowson contacted an background, to join the new diamond
10 Chemistry Explored // Issue 2 INNOVATION
group as its first postdoctoral researcher. Twent y-three 1894 years later he now Science-fiction runs the diamond visionary HG lab with Professor Wells publishes Ashfold and Dr the short story, Neil Fox from the The Diamond School of Physics. Maker, about the The lab is now the lead character’s only chemistry- attempts to based synthetic make artificial diamond lab in the diamonds. United Kingdom. One of Professor May’s primary interests has been in understanding the heat conductivity, Molecules That Amaze Us fundamental chemistry of diamond growth you have the recipe in a technique known as chemical vapour for a substance When not working on scientific deposition (CVD). This is one of the with a huge 1954 problems that sound like main techniques for growing diamonds, number of potential Tracy Hall at something out of a sci-fi film, the other being high temperature, high applications, such as General Electric Professor Paul May has been pressure (HPHT) techniques, which electronic devices, produces the first working hard on his new book, mimic the conditions in the Earth that lead sensors, displays commercially Molecules That Amaze Us. to the natural formation of diamonds. and electrochemical successful Each chapter will feature However, whilst HPHT techniques are electrodes. synthesis of a different molecule, with excellent for making ‘industrial’ diamonds One application diamond. information on its chemistry for coating saw blades or drill bits, there for these boron- and importance, written in an are some advantages to not having to use doped diamond films that Professor accessible and engaging style. such extreme pressure and temperature May is particularly excited about is in The format of the book will be conditions in the synthetic process. human medicine. At present, one of the familiar to fans of Professor With CVD, it is possible to grow few surgical options available for the May’s ‘Molecule of the Month’ thin films of diamond that can be less management of Parkinson’s symptoms is webpage (www.chm.bris.ac.uk/ than a few micrometres thick that are deep brain stimulation, a process which motm/motm.htm) but the book exceptionally pure. The technique works involves the implantation of electrodes into will feature additional content, by flowing a hydrocarbon gas mixture the brain that send out electrical impulses. cartoons and plenty of historical over a heated filament. The hydrocarbon The chemical composition of diamond anecdotes. molecules will react and decompose on means it is one of few materials that do Molecules That Amaze Us is coming into contact with the filament, not trigger an immune response when due for and then deposit onto a nearby substrate to implanted into the body. When this is publication gradually build up a coating of diamond on combined with the conductive abilities of in a few the surface. boron-doped diamond films, using these months, just Much of this excitement stems from the as an alternative to metal electrodes could in time to excellent conductive have a revolutionary be a perfect properties of boron- impact for Parkinson’s Christmas doped diamond. When patients, who could gift for you couple this with 1970 have diamond all those many of the unique The first synthetic gem-quality electrodes implanted chemists properties of diamond, diamond crystals are produced which last decades or you know its robustness, chemical by General Electric. even the lifetime of and love. inertness and excellent the patient.
Chemistry Explored // Issue 2 11 OUTREACH
Hops are the female flowers of the hop plant, Humulus lupulus
Hops and beer - a bitter relationship
The school’s Picture It… Chemistry blog delves deep into the chemistry of everyday substances. Here, Ben Mills looks at that staple of the British diet – beer. Here’s an extract…
H Hops (Humulus lupulus) eer is an important part of our They clarify the beer, act as an antibiotic H civilisation. It’s been brewed to preserve it, help to create the foam H caryophyllenH e across the world for thousands of and are mainly responsible its aroma, humulene myrcene H B humulene myrcene caryophyllene years as the alcohol content prevents the flavour and bitterness. But where does H growth of microorganisms responsible the bitter taste actually come from? humulene myrcene caryophyllene for diseases caught from drinking dirty To understand this, we need to know how water. Nowadays water treatment purifies beer is made. Skeletal formula of the hop terpenes humulene, myrcene and caryophyllene. drinking water, but thanks to its long The most important brewing steps are history, brewing beer has remained part mashing, boiling and fermenting. OH OOH O O of our culture and is now a major part of During mashing the starch in malt is O OO our economy. broken down into sugars by naturally HO O HO O HO OH HO OH Since the 19th century, brewing has present enzymes called amylases. During OH O OH O OH O evolved from a domestic to an industrial boiling, the sugary solution is boiled O O humulone isohumulone enterprise, and over the years we have with hops to remove some of the water humulone isohumulone O learnt a great deal about the chemistry of and destroy the enzymes. Finally comes HO HO Skeletal formulaeOH of humulone and isohumulone, twoOH substances responsible for the bitter taste of beer. one of beer’s main ingredients: hops. fermenting. The solution is cooled and O Not only do hops contain a huge variety yeast is added, converting the sugars into
alkenes humulone alkanesisohumulone of compounds, but also the same chemicals ethanol (alcohol) and carbon dioxide. that give beer its flavour may become the Both sugars (small soluble molecules) O O alkenes 1 atm H2 (g) O O 10% Pd/C alkanes medicines of tomorrow. and starch (an insoluble polymer) are MeOH O HO O OH 1 atm H2 (g) HO O carbohydrates composed of carbon, OHO O 10% Pd/C 80-95% yield O MeOH Beer today hydrogen and oxygen in a 1:2:1 ratio. HO tetrahydroisohumlone OHisohumulone HO These days, beer is made from dried, Carbohydrates are used by living alkenes OH O alkanes Isohumulone (left) 80-95%can be y ielreducedd to O germinated barley (malt), yeast, water organisms to store energy and release it on tetrahydroisohumulone (right) by hydrogen gas with a solid O O isohumulonpalladium-on-carbone 1 catalystatm H2 (g) suspended tinetra methanol.hyOdroisohumloneO and hops. These dried cone-shaped flowers demand. The starch, a long chain of sugar Alkene groups in the 10%prenyl Pd/C side chains of isohumulone MeOH of the hop plant, Humulus lupulus, were molecules linked together by carbon- HO are reduced to alkanes. OH HO added to beer from the middle ages. oxygen bonds, is broken down to sugars OH O 80-95% yield O
isohumulon12 Chemistrye Explored // Issue t2etrahydroisohumlone SINCE THE 19TH About the Picture It… Chemistry blog CENTURY, BREWING Dr Jenny Slaughter and Dr Natalie Fey started the Picture It... Chemistry blog as a means of talking about science in a way that anyone can HAS EVOLVED FROM understand. Each post is written by a collaborative team, bringing together A DOMESTIC TO research and ideas from technicians, administrative staff, academics, undergraduates, postgraduates AN INDUSTRIAL and school students. As well ENTERPRISE as beer, other recent postings comment on diverse topics when energy is required, while the sugars including the properties of are put through a cascade of biochemical marmalade, spearmint, bananas reactions to release their energy. When no and aloe vera. oxygen is available (anaerobic conditions), only products containing the same amount You can read the blog in full at of oxygen as the sugar contains can be chempics.wordpress.com generated – this is fermentation. In human muscle, sugars ferment to lactic acid, causing cramp. In yeast, sugars ferment to ethanol and carbon dioxide. derivatives – tetrahydroisohumulones – can be added to the beer later to reach The boiling stage Meet the chemist Hops flowers contain a family of the desired degree of bitterness. While compounds called alpha-acids or isohumulones are the main source of humulones, which are organic molecules bitterness in beer, hops provide many other Ben Mills containing a ring of six carbon atoms. compounds that create the rich aroma When heated, humulones undergo a and taste of beer. More than 150 fragrant reaction called an acyloin rearrangement, molecules are present in hop oil, including producing a new family of compounds - some found in spices and flowers – grassy- the iso-alpha-acids or isohumulones. smelling aldehydes, citrusy esters, floral These contain a smaller ring of five and fruity geraniol and herbal oxidised carbon atoms. During the boiling stage of sesquiterpenes. brewing, the high temperature converts humulones to isohumulones, developing Cancer prevention the distinctive bitter flavour of beer. Several compounds in beer are Isohumulones tend to react further, being investigated as they may help often decomposing to other isomers, prevent cancer and treat diabetes and oxidising or forming polymers. To avoid inflammation. this instability, some breweries convert Meanwhile, humulone also shows isohumulones into more stable compounds promising anti-cancer properties. by extracting the isohumulones from hops Its precise structure was revealed in and carrying out hydrogenation. Stable an American research article, helping Ben Mills is a postgraduate scientists to student in the group of Dr Charl hopefully develop Faul. In between contributing medicines based to Picture It…, he manages to on molecules find time to work on his PhD from hops. research, investigating organic Too good to compounds for use as materials be true? For in electronic devices. Ben recently anyone hoping to returned from Japan, where he avoid cancer by was working with chemists at heading to the Kyoto University on a joint project pub, the authors involving polymerisation reactions were keen to in liquid crystal solvents. He point out that also demonstrates experiments “excessive beer at schools and in the second consumption year undergraduate teaching Hops in a box of ethanol cannot be laboratories. Outside of work, he wash bottles with molecular recommended enjoys climbing and pub quizzes, structures of humulone (left) and isohumulone (right) to propagate and attempts to play badminton.
good health”. theTake challenge: The correct answer is the left-hand side molecule,Whilst commercially both molecules known fulfil as Prozac, the oftenrequired used inproperties, the treatment it ofis a depression.dye, called Red-2G present in the right-hand side molecule, which is toxic if consumed.
Chemistry Explored // Issue 2 13 INSIDE VIEW Meet the porter Chemistry Explored hooks up with Jon May, the first point of contact for school newcomers
IT’S LATE JUNE, and School of Chemistry porter Jon May is enjoying the relaxed atmosphere of campus in summer, compared to the business of term time, when about 800 students can descend on the building at once. This is the calm before the storm, he jokes. As the welcoming face of the school, he is the first point of contact for many students when they arrive, full of questions and queuing down the corridor. “In term-time it’s heaving,” he explains. “It gets a bit crazy when you’ve got one class going out and another one coming in, but it’s nice to be busy.” And, after working in the school for four-and-a- half years, there isn’t much he doesn’t know about its inner workings. “The autumn term is the busiest time of year – it’s manic.” And it’s busier than ever since the schools started sharing lecture space. “We get to know the chemists, but now we have students from across the university here, there are even more people coming in and out.” After doing the rounds, Jon’s duties include disposing of glass waste from the labs, manning reception and welcoming visitors, including on one occasion the Mayor of Bristol, George Ferguson, who was giving a lecture. “I was only planning on being here for six months,” he says, “but I’ll have been here 15 years soon!” After starting at the School of Veterinary Sciences, Jon moved to Engineering and then the Students’ Union, before coming to Chemistry for a promotion. “Things in Chemistry are relatively tame compared to the union building,” he says, remembering one occasion when the BBC medical drama Casualty was filming there. “They changed the sign on the front, and a girl walked past and said in all seriousness, ‘When did the union become a hospital?’” As we go to press, the students will soon be returning, and Jon is looking forward to the influx; working closely with the staff and students is his favourite part of the job. “It’s the people “THE AUTUMN that make it,” he says. TERM IS THE BUSIEST OF THE YEAR – IT’S MANIC”
Jon May has worked at the School of Chemistry for four- and-a-half years
14 Chemistry Explored // Issue 2 INFOGRAPHIC Meet the porter CHEMISTRY in numbers 1,000 km the total length of superconducting wire (mainly 2,000 L Nb3Sn and NbTi) contained in our NMR magnets. the quantity of liquid Helium we use to fill our NMR magnets every year (for a price comparison – you could pour in one bottle of award-winning Scotch whisky every day for the same cost… that’s one shot an hour, all day, every day!). 12 The number of NMR spectrometers we will have in the School of Chemistry by early 2015. 400 The NMR magnets generate their enormous magnetic fields using superconducting wire that is cooled to just The number of party balloons you could fill with the 4 degrees kelvin above absolute zero, or helium boil-off gas from our NMR magnets every day. And as it takes around 4,000 party balloons to lift the average person off the ground, you could achieve that goal in about 10 days if you put your mind to it. -269 °C We also use sensitive electronic receivers that are kept very cold – one of our probes runs at the same We purchase and recycle nearly temperature as the surface of the planet Pluto at only 20 kelvin. 8,000 The temperature inside the magnet is over Winchester solvent bottles a year.
In 2013 we disposed of 10 0 °C 3 6 , 2 4 0 L colder than the coldest ever recorded on Earth. of solvent waste – all of which was recycled and reused as an alternative fuel source in things like cement kilns. 4,000 boxes of disposable gloves used per year. 7.8G Wh used each year in the school, the same as 50-80 1,600 homes and 20% of the precinct total. parcels received daily from suppliers.
Chemistry Explored // Issue 2 15 Life through a lens
Chem@rt is a University of Bristol initiative that brings chemistry into the classroom and stimulates literacy and creativity. Here are a small selection of the stunning images created by our scientists
Frog Chorus by Dr Simon Hall These are Bryozoa – coral-like animals which live on seaweed and rocks (and any passing ships!). These micro-organisms construct amazingly complex, chalky shells to provide individual compartments in which each animal lives. Some colonies can grow many metres in size, containing millions of individuals.
Bundles of Gold by Geri Echue Fantastic Voyage by Professor Mike Ashfold This is a Polarised Light Microscopy image of a liquid- When an individual molecule absorbs light it may gain crystalline material. Liquid crystals are an odd state of matter enough energy to break up into smaller molecules or that sometimes behave a like a solid and sometimes like a atoms. The different rings in this image show all the liquid. They will flow like a liquid, but their particles line up different energies of the products formed. Analysis of such in an ordered fashion, like a solid. They are used in many images can provide a very detailed understanding of the electronic displays, like flatscreen televisions. chemical bonds which hold molecules together.
Look out for the next issue of Chemistry Explored for images on the theme of catalysis. Send your entries to [email protected], including a JPEG image, a brief caption, and your name and address.